1. Field of the Invention
The present invention generally relates to user interfaces for sensory surfaces. More particularly, the invention relates to user interfaces for sensory surfaces having touch-sensitive functionality.
2. Description of Related Art
Display screens of electronic devices often include user interfaces, through which the user can make selections related to various images displayed on the display screen. For example, on a mobile telephone, a user types a telephone number using keys, which causes the telephone number to be displayed on the screen. When the user presses a “call” or “talk” button, the screen shows that the telephone is proceeding to dial the number entered.
Current display applications can generally be categorized into two major types: 1) display screens with off-screen, hard-button controls, and 2) display screens with touch screen capability. Some devices allow use of both types of functionality. For example, a personal digital assistant (PDA) may allow a user to select images either by use of a touch screen or by use of a hard button. Other devices have provided some integration of hard and soft features by locating hard buttons next to a screen, such that a hard button may be pushed in order to select an icon located on the display screen adjacent to the hard button.
Touch screens may allow a greater amount of functionality than hard buttons because the displays provided by the software can be changed throughout different navigation screens, which allows more customization and configurability with different functionality on different screens. The software program can properly re-label each touch screen selection button as the user navigates through various touch screens, which saves the user from having to use “shift” functions/operations and keeps the number of necessary hard buttons to a minimum.
However, touch screens may be more difficult for users to operate than conventional hard buttons, because a user may have difficulty determining exactly where the touch screen button is located or how far to move a slide-type button or box across a display screen to obtain the desired functionality. In other words, a user may have difficulty determining the location of the touch screen virtual button. This difficulty may occur because the user does not receive the same type of sensory feedback from a touch screen that the user would receive from hard buttons (the feeling of a detent, or the sound of several rotary clicks, for example) and from the fact that if the touch screen is integrated into an automobile, the user may not be looking directly at the touch screen. In other words, dedicated touch screen functions occupy a higher degree of a user's visual load and attention load than hard buttons or rotary knobs do.
A device that requires a high degree of a user's visual, attention, or cognitive load is problematic because users desire to operate several devices simultaneously and/or attend to a primary task without having to dedicate all of their visual senses to one device. For example, a user may desire to increase the volume on a hands-free speaker phone while driving a vehicle. If the volume function exists only as a virtual slide button on a touch-screen, the user may have difficulty locating and safely sliding the virtual volume button to the desired level while attending to the primary task of driving.
In view of the above, it is apparent that there exists a need for a touch-sensitive user interface that lends itself to non-visual use.